Turkish officials announced on Thursday that the vaccine from the Chinese company Sinovac has an effective rate of 91.25%, but this finding is based on preliminary results from a small clinical trial. No data has been published in journals or online.
The announcement comes the day before another ambiguous press conference about the Sinovac vaccine in Brazil. Officials there are expected to provide detailed results of another trial, but only reported that the vaccine is more than 50% effective.
A total of 7,371 volunteers participated in the Turkish trial, but the efficacy data presented by infectious disease expert Serhat Unal was only based on 1
Dr. Unal said that the 26 volunteers who received the placebo contracted Covid-19, while only 3 vaccinated volunteers became ill. He and his colleagues did not share their data in writing.
Health Minister Fahrettin Koca said: “Now, we are convinced that this vaccine is effective and safe for the Turkish people.”
Sinovac did not issue a public statement about the trial, nor did it comment on the Brazilian trial.
A small number of volunteers calculated by Turkish researchers based on their utility raised questions about the certainty of their conclusions. The more people participating in clinical vaccine trials, the stronger their statistical power.
In contrast, Pfizer and BioNTech provided data on 36,523 people, indicating that the vaccine is 95% effective. For their vaccine, 162 people who received a placebo developed Covid, while only 8 people who received the vaccine.
Turkey and Sinovac signed an agreement for 50 million doses of vaccine. Koka said the first three million doses are scheduled to arrive in Turkey on Monday. Mr. Koca said that by the end of March, Turkey will receive 4.5 million doses of Pfizer-BioNTech vaccine. He said that by the end of January there will be about one million doses.
Sinovac calls its vaccine CoronaVac, which is made from a killed coronavirus. This method is one of the oldest vaccine production methods and was used by Jonas Salk to make polio vaccines in the 1950s. After the viruses are inactivated with chemicals, they will not make people sick, but they can stimulate the immune system to produce antibodies, which can resist live viruses for a long time.
Sinovac developed CoronaVac in early 2020 and then conducted a series of clinical trials. They released the results in November. They reported there that the vaccine appeared to be safe and triggered an immune response against the coronavirus.
Subsequently, the company conducted phase 3 trials in Brazil, Indonesia and Turkey, three countries with high Covid-19 rates.
Brazilian health officials said on Wednesday that the Chinese vaccine has passed safety and effectiveness tests, which will pave the way for its use in Brazil, but they cited a contract agreement with Sinovac to postpone the release of detailed data on Brazilian clinical trials as a basis. . Dimas Covas, director of the Butantan Institute, which conducted the trial, said the joint announcement could happen within two weeks.
São Paulo State Health Minister Jean Gorinchteyn told reporters at a press conference: “Today is a historic day for science and Brazilian health.” “This will allow us to save hundreds of people. The lives of ten thousand people are not only in Brazil but in the whole world.”